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#include <climits> // INT_MAX
#include <cmath>
#include <algorithm>
#define NAPI_EXPERIMENTAL
#include "env-inl.h"
#include "js_native_api_v8.h"
#include "js_native_api.h"
#include "util-inl.h"
#define CHECK_MAYBE_NOTHING(env, maybe, status) \
RETURN_STATUS_IF_FALSE((env), !((maybe).IsNothing()), (status))
#define CHECK_MAYBE_NOTHING_WITH_PREAMBLE(env, maybe, status) \
RETURN_STATUS_IF_FALSE_WITH_PREAMBLE((env), !((maybe).IsNothing()), (status))
#define CHECK_TO_NUMBER(env, context, result, src) \
CHECK_TO_TYPE((env), Number, (context), (result), (src), napi_number_expected)
// n-api defines NAPI_AUTO_LENGHTH as the indicator that a string
// is null terminated. For V8 the equivalent is -1. The assert
// validates that our cast of NAPI_AUTO_LENGTH results in -1 as
// needed by V8.
#define CHECK_NEW_FROM_UTF8_LEN(env, result, str, len) \
do { \
static_assert(static_cast<int>(NAPI_AUTO_LENGTH) == -1, \
"Casting NAPI_AUTO_LENGTH to int must result in -1"); \
RETURN_STATUS_IF_FALSE((env), \
(len == NAPI_AUTO_LENGTH) || len <= INT_MAX, \
napi_invalid_arg); \
RETURN_STATUS_IF_FALSE((env), \
(str) != nullptr, \
napi_invalid_arg); \
auto str_maybe = v8::String::NewFromUtf8( \
(env)->isolate, (str), v8::NewStringType::kInternalized, \
static_cast<int>(len)); \
CHECK_MAYBE_EMPTY((env), str_maybe, napi_generic_failure); \
(result) = str_maybe.ToLocalChecked(); \
} while (0)
#define CHECK_NEW_FROM_UTF8(env, result, str) \
CHECK_NEW_FROM_UTF8_LEN((env), (result), (str), NAPI_AUTO_LENGTH)
#define CREATE_TYPED_ARRAY( \
env, type, size_of_element, buffer, byte_offset, length, out) \
do { \
if ((size_of_element) > 1) { \
THROW_RANGE_ERROR_IF_FALSE( \
(env), (byte_offset) % (size_of_element) == 0, \
"ERR_NAPI_INVALID_TYPEDARRAY_ALIGNMENT", \
"start offset of "#type" should be a multiple of "#size_of_element); \
} \
THROW_RANGE_ERROR_IF_FALSE((env), (length) * (size_of_element) + \
(byte_offset) <= buffer->ByteLength(), \
"ERR_NAPI_INVALID_TYPEDARRAY_LENGTH", \
"Invalid typed array length"); \
(out) = v8::type::New((buffer), (byte_offset), (length)); \
} while (0)
namespace v8impl {
namespace {
inline static napi_status
V8NameFromPropertyDescriptor(napi_env env,
const napi_property_descriptor* p,
v8::Local<v8::Name>* result) {
if (p->utf8name != nullptr) {
CHECK_NEW_FROM_UTF8(env, *result, p->utf8name);
} else {
v8::Local<v8::Value> property_value =
v8impl::V8LocalValueFromJsValue(p->name);
RETURN_STATUS_IF_FALSE(env, property_value->IsName(), napi_name_expected);
*result = property_value.As<v8::Name>();
}
return napi_ok;
}
// convert from n-api property attributes to v8::PropertyAttribute
inline static v8::PropertyAttribute V8PropertyAttributesFromDescriptor(
const napi_property_descriptor* descriptor) {
unsigned int attribute_flags = v8::PropertyAttribute::None;
// The napi_writable attribute is ignored for accessor descriptors, but
// V8 would throw `TypeError`s on assignment with nonexistence of a setter.
if ((descriptor->getter == nullptr && descriptor->setter == nullptr) &&
(descriptor->attributes & napi_writable) == 0) {
attribute_flags |= v8::PropertyAttribute::ReadOnly;
}
if ((descriptor->attributes & napi_enumerable) == 0) {
attribute_flags |= v8::PropertyAttribute::DontEnum;
}
if ((descriptor->attributes & napi_configurable) == 0) {
attribute_flags |= v8::PropertyAttribute::DontDelete;
}
return static_cast<v8::PropertyAttribute>(attribute_flags);
}
inline static napi_deferred
JsDeferredFromNodePersistent(v8impl::Persistent<v8::Value>* local) {
return reinterpret_cast<napi_deferred>(local);
}
inline static v8impl::Persistent<v8::Value>*
NodePersistentFromJsDeferred(napi_deferred local) {
return reinterpret_cast<v8impl::Persistent<v8::Value>*>(local);
}
class HandleScopeWrapper {
public:
explicit HandleScopeWrapper(v8::Isolate* isolate) : scope(isolate) {}
private:
v8::HandleScope scope;
};
// In node v0.10 version of v8, there is no EscapableHandleScope and the
// node v0.10 port use HandleScope::Close(Local<T> v) to mimic the behavior
// of a EscapableHandleScope::Escape(Local<T> v), but it is not the same
// semantics. This is an example of where the api abstraction fail to work
// across different versions.
class EscapableHandleScopeWrapper {
public:
explicit EscapableHandleScopeWrapper(v8::Isolate* isolate)
: scope(isolate), escape_called_(false) {}
bool escape_called() const {
return escape_called_;
}
template <typename T>
v8::Local<T> Escape(v8::Local<T> handle) {
escape_called_ = true;
return scope.Escape(handle);
}
private:
v8::EscapableHandleScope scope;
bool escape_called_;
};
inline static napi_handle_scope
JsHandleScopeFromV8HandleScope(HandleScopeWrapper* s) {
return reinterpret_cast<napi_handle_scope>(s);
}
inline static HandleScopeWrapper*
V8HandleScopeFromJsHandleScope(napi_handle_scope s) {
return reinterpret_cast<HandleScopeWrapper*>(s);
}
inline static napi_escapable_handle_scope
JsEscapableHandleScopeFromV8EscapableHandleScope(
EscapableHandleScopeWrapper* s) {
return reinterpret_cast<napi_escapable_handle_scope>(s);
}
inline static EscapableHandleScopeWrapper*
V8EscapableHandleScopeFromJsEscapableHandleScope(
napi_escapable_handle_scope s) {
return reinterpret_cast<EscapableHandleScopeWrapper*>(s);
}
inline static napi_status ConcludeDeferred(napi_env env,
napi_deferred deferred,
napi_value result,
bool is_resolved) {
NAPI_PREAMBLE(env);
CHECK_ARG(env, result);
v8::Local<v8::Context> context = env->isolate->GetCurrentContext();
v8impl::Persistent<v8::Value>* deferred_ref =
NodePersistentFromJsDeferred(deferred);
v8::Local<v8::Value> v8_deferred =
v8::Local<v8::Value>::New(env->isolate, *deferred_ref);
auto v8_resolver = v8::Local<v8::Promise::Resolver>::Cast(v8_deferred);
v8::Maybe<bool> success = is_resolved ?
v8_resolver->Resolve(context, v8impl::V8LocalValueFromJsValue(result)) :
v8_resolver->Reject(context, v8impl::V8LocalValueFromJsValue(result));
delete deferred_ref;
RETURN_STATUS_IF_FALSE(env, success.FromMaybe(false), napi_generic_failure);
return GET_RETURN_STATUS(env);
}
class ArrayBufferReference final : public Reference {
public:
// Same signatures for ctor and New() as Reference, except this only works
// with ArrayBuffers:
template <typename... Args>
explicit ArrayBufferReference(napi_env env,
v8::Local<v8::ArrayBuffer> value,
Args&&... args)
: Reference(env, value, std::forward<Args>(args)...) {}
template <typename... Args>
static ArrayBufferReference* New(napi_env env,
v8::Local<v8::ArrayBuffer> value,
Args&&... args) {
return new ArrayBufferReference(env, value, std::forward<Args>(args)...);
}
private:
inline void Finalize(bool is_env_teardown) override {
if (is_env_teardown) {
v8::HandleScope handle_scope(_env->isolate);
v8::Local<v8::Value> obj = Get();
CHECK(!obj.IsEmpty());
CHECK(obj->IsArrayBuffer());
v8::Local<v8::ArrayBuffer> ab = obj.As<v8::ArrayBuffer>();
if (ab->IsDetachable())
ab->Detach();
}
Reference::Finalize(is_env_teardown);
}
};
enum UnwrapAction {
KeepWrap,
RemoveWrap
};
inline static napi_status Unwrap(napi_env env,
napi_value js_object,
void** result,
UnwrapAction action) {
NAPI_PREAMBLE(env);
CHECK_ARG(env, js_object);
if (action == KeepWrap) {
CHECK_ARG(env, result);
}
v8::Isolate* isolate = env->isolate;
v8::Local<v8::Context> context = isolate->GetCurrentContext();
v8::Local<v8::Value> value = v8impl::V8LocalValueFromJsValue(js_object);
RETURN_STATUS_IF_FALSE(env, value->IsObject(), napi_invalid_arg);
v8::Local<v8::Object> obj = value.As<v8::Object>();
auto val = obj->GetPrivate(context, NAPI_PRIVATE_KEY(context, wrapper))
.ToLocalChecked();
RETURN_STATUS_IF_FALSE(env, val->IsExternal(), napi_invalid_arg);
Reference* reference =
static_cast<v8impl::Reference*>(val.As<v8::External>()->Value());
if (result) {
*result = reference->Data();
}
if (action == RemoveWrap) {
CHECK(obj->DeletePrivate(context, NAPI_PRIVATE_KEY(context, wrapper))
.FromJust());
Reference::Delete(reference);
}
return GET_RETURN_STATUS(env);
}
//=== Function napi_callback wrapper =================================
// Use this data structure to associate callback data with each N-API function
// exposed to JavaScript. The structure is stored in a v8::External which gets
// passed into our callback wrapper. This reduces the performance impact of
// calling through N-API.
// Ref: benchmark/misc/function_call
// Discussion (incl. perf. data): https://github.com/nodejs/node/pull/21072
struct CallbackBundle {
napi_env env; // Necessary to invoke C++ NAPI callback
void* cb_data; // The user provided callback data
napi_callback function_or_getter;
napi_callback setter;
};
// Base class extended by classes that wrap V8 function and property callback
// info.
class CallbackWrapper {
public:
CallbackWrapper(napi_value this_arg, size_t args_length, void* data)
: _this(this_arg), _args_length(args_length), _data(data) {}
virtual napi_value GetNewTarget() = 0;
virtual void Args(napi_value* buffer, size_t bufferlength) = 0;
virtual void SetReturnValue(napi_value value) = 0;
napi_value This() { return _this; }
size_t ArgsLength() { return _args_length; }
void* Data() { return _data; }
protected:
const napi_value _this;
const size_t _args_length;
void* _data;
};
template <typename Info, napi_callback CallbackBundle::*FunctionField>
class CallbackWrapperBase : public CallbackWrapper {
public:
CallbackWrapperBase(const Info& cbinfo, const size_t args_length)
: CallbackWrapper(JsValueFromV8LocalValue(cbinfo.This()),
args_length,
nullptr),
_cbinfo(cbinfo) {
_bundle = reinterpret_cast<CallbackBundle*>(
v8::Local<v8::External>::Cast(cbinfo.Data())->Value());
_data = _bundle->cb_data;
}
napi_value GetNewTarget() override { return nullptr; }
protected:
void InvokeCallback() {
napi_callback_info cbinfo_wrapper = reinterpret_cast<napi_callback_info>(
static_cast<CallbackWrapper*>(this));
// All other pointers we need are stored in `_bundle`
napi_env env = _bundle->env;
napi_callback cb = _bundle->*FunctionField;
napi_value result;
env->CallIntoModule([&](napi_env env) {
result = cb(env, cbinfo_wrapper);
});
if (result != nullptr) {
this->SetReturnValue(result);
}
}
const Info& _cbinfo;
CallbackBundle* _bundle;
};
class FunctionCallbackWrapper
: public CallbackWrapperBase<v8::FunctionCallbackInfo<v8::Value>,
&CallbackBundle::function_or_getter> {
public:
static void Invoke(const v8::FunctionCallbackInfo<v8::Value>& info) {
FunctionCallbackWrapper cbwrapper(info);
cbwrapper.InvokeCallback();
}
explicit FunctionCallbackWrapper(
const v8::FunctionCallbackInfo<v8::Value>& cbinfo)
: CallbackWrapperBase(cbinfo, cbinfo.Length()) {}
napi_value GetNewTarget() override {
if (_cbinfo.IsConstructCall()) {
return v8impl::JsValueFromV8LocalValue(_cbinfo.NewTarget());
} else {
return nullptr;
}
}
/*virtual*/
void Args(napi_value* buffer, size_t buffer_length) override {
size_t i = 0;
size_t min = std::min(buffer_length, _args_length);
for (; i < min; i += 1) {
buffer[i] = v8impl::JsValueFromV8LocalValue(_cbinfo[i]);
}
if (i < buffer_length) {
napi_value undefined =
v8impl::JsValueFromV8LocalValue(v8::Undefined(_cbinfo.GetIsolate()));
for (; i < buffer_length; i += 1) {
buffer[i] = undefined;
}
}
}
/*virtual*/
void SetReturnValue(napi_value value) override {
v8::Local<v8::Value> val = v8impl::V8LocalValueFromJsValue(value);
_cbinfo.GetReturnValue().Set(val);
}
};
class GetterCallbackWrapper
: public CallbackWrapperBase<v8::PropertyCallbackInfo<v8::Value>,
&CallbackBundle::function_or_getter> {
public:
static void Invoke(v8::Local<v8::Name> property,
const v8::PropertyCallbackInfo<v8::Value>& info) {
GetterCallbackWrapper cbwrapper(info);
cbwrapper.InvokeCallback();
}
explicit GetterCallbackWrapper(
const v8::PropertyCallbackInfo<v8::Value>& cbinfo)
: CallbackWrapperBase(cbinfo, 0) {}
/*virtual*/
void Args(napi_value* buffer, size_t buffer_length) override {
if (buffer_length > 0) {
napi_value undefined =
v8impl::JsValueFromV8LocalValue(v8::Undefined(_cbinfo.GetIsolate()));
for (size_t i = 0; i < buffer_length; i += 1) {
buffer[i] = undefined;
}
}
}
/*virtual*/
void SetReturnValue(napi_value value) override {
v8::Local<v8::Value> val = v8impl::V8LocalValueFromJsValue(value);
_cbinfo.GetReturnValue().Set(val);
}
};
class SetterCallbackWrapper
: public CallbackWrapperBase<v8::PropertyCallbackInfo<void>,
&CallbackBundle::setter> {
public:
static void Invoke(v8::Local<v8::Name> property,
v8::Local<v8::Value> value,
const v8::PropertyCallbackInfo<void>& info) {
SetterCallbackWrapper cbwrapper(info, value);
cbwrapper.InvokeCallback();
}
SetterCallbackWrapper(const v8::PropertyCallbackInfo<void>& cbinfo,
const v8::Local<v8::Value>& value)
: CallbackWrapperBase(cbinfo, 1), _value(value) {}
/*virtual*/
void Args(napi_value* buffer, size_t buffer_length) override {
if (buffer_length > 0) {
buffer[0] = v8impl::JsValueFromV8LocalValue(_value);
if (buffer_length > 1) {
napi_value undefined = v8impl::JsValueFromV8LocalValue(
v8::Undefined(_cbinfo.GetIsolate()));
for (size_t i = 1; i < buffer_length; i += 1) {
buffer[i] = undefined;
}
}
}
}
/*virtual*/
void SetReturnValue(napi_value value) override {
// Ignore any value returned from a setter callback.
}
private:
const v8::Local<v8::Value>& _value;
};
static void DeleteCallbackBundle(napi_env env, void* data, void* hint) {
CallbackBundle* bundle = static_cast<CallbackBundle*>(data);
delete bundle;
}
// Creates an object to be made available to the static function callback
// wrapper, used to retrieve the native callback function and data pointer.
static
v8::Local<v8::Value> CreateFunctionCallbackData(napi_env env,
napi_callback cb,
void* data) {
CallbackBundle* bundle = new CallbackBundle();
bundle->function_or_getter = cb;
bundle->cb_data = data;
bundle->env = env;
v8::Local<v8::Value> cbdata = v8::External::New(env->isolate, bundle);
Reference::New(env, cbdata, 0, true, DeleteCallbackBundle, bundle, nullptr);
return cbdata;
}
enum WrapType {
retrievable,
anonymous
};
template <WrapType wrap_type>
inline napi_status Wrap(napi_env env,
napi_value js_object,
void* native_object,
napi_finalize finalize_cb,
void* finalize_hint,
napi_ref* result) {
NAPI_PREAMBLE(env);
CHECK_ARG(env, js_object);
v8::Local<v8::Context> context = env->context();
v8::Local<v8::Value> value = v8impl::V8LocalValueFromJsValue(js_object);
RETURN_STATUS_IF_FALSE(env, value->IsObject(), napi_invalid_arg);
v8::Local<v8::Object> obj = value.As<v8::Object>();
if (wrap_type == retrievable) {
// If we've already wrapped this object, we error out.
RETURN_STATUS_IF_FALSE(env,
!obj->HasPrivate(context, NAPI_PRIVATE_KEY(context, wrapper))
.FromJust(),
napi_invalid_arg);
} else if (wrap_type == anonymous) {
// If no finalize callback is provided, we error out.
CHECK_ARG(env, finalize_cb);
}
v8impl::Reference* reference = nullptr;
if (result != nullptr) {
// The returned reference should be deleted via napi_delete_reference()
// ONLY in response to the finalize callback invocation. (If it is deleted
// before then, then the finalize callback will never be invoked.)
// Therefore a finalize callback is required when returning a reference.
CHECK_ARG(env, finalize_cb);
reference = v8impl::Reference::New(
env, obj, 0, false, finalize_cb, native_object, finalize_hint);
*result = reinterpret_cast<napi_ref>(reference);
} else {
// Create a self-deleting reference.
reference = v8impl::Reference::New(env, obj, 0, true, finalize_cb,
native_object, finalize_cb == nullptr ? nullptr : finalize_hint);
}
if (wrap_type == retrievable) {
CHECK(obj->SetPrivate(context, NAPI_PRIVATE_KEY(context, wrapper),
v8::External::New(env->isolate, reference)).FromJust());
}
return GET_RETURN_STATUS(env);
}
} // end of anonymous namespace
// Wrapper around v8impl::Persistent that implements reference counting.
RefBase::RefBase(napi_env env,
uint32_t initial_refcount,
bool delete_self,
napi_finalize finalize_callback,
void* finalize_data,
void* finalize_hint)
: Finalizer(env, finalize_callback, finalize_data, finalize_hint),
_refcount(initial_refcount),
_delete_self(delete_self) {
Link(finalize_callback == nullptr ? &env->reflist : &env->finalizing_reflist);
}
RefBase* RefBase::New(napi_env env,
uint32_t initial_refcount,
bool delete_self,
napi_finalize finalize_callback,
void* finalize_data,
void* finalize_hint) {
return new RefBase(env,
initial_refcount,
delete_self,
finalize_callback,
finalize_data,
finalize_hint);
}
RefBase::~RefBase() {
Unlink();
}
void* RefBase::Data() {
return _finalize_data;
}
// Delete is called in 2 ways. Either from the finalizer or
// from one of Unwrap or napi_delete_reference.
//
// When it is called from Unwrap or napi_delete_reference we only
// want to do the delete if the finalizer has already run or
// cannot have been queued to run (ie the reference count is > 0),
// otherwise we may crash when the finalizer does run.
// If the finalizer may have been queued and has not already run
// delay the delete until the finalizer runs by not doing the delete
// and setting _delete_self to true so that the finalizer will
// delete it when it runs.
//
// The second way this is called is from
// the finalizer and _delete_self is set. In this case we
// know we need to do the deletion so just do it.
void RefBase::Delete(RefBase* reference) {
if ((reference->RefCount() != 0) || (reference->_delete_self) ||
(reference->_finalize_ran)) {
delete reference;
} else {
// defer until finalizer runs as
// it may already be queued
reference->_delete_self = true;
}
}
uint32_t RefBase::Ref() {
return ++_refcount;
}
uint32_t RefBase::Unref() {
if (_refcount == 0) {
return 0;
}
return --_refcount;
}
uint32_t RefBase::RefCount() {
return _refcount;
}
void RefBase::Finalize(bool is_env_teardown) {
// In addition to being called during environment teardown, this method is
// also the entry point for the garbage collector. During environment
// teardown we have to remove the garbage collector's reference to this
// method so that, if, as part of the user's callback, JS gets executed,
// resulting in a garbage collection pass, this method is not re-entered as
// part of that pass, because that'll cause a double free (as seen in
// https://github.com/nodejs/node/issues/37236).
//
// Since this class does not have access to the V8 persistent reference,
// this method is overridden in the `Reference` class below. Therein the
// weak callback is removed, ensuring that the garbage collector does not
// re-enter this method, and the method chains up to continue the process of
// environment-teardown-induced finalization.
// During environment teardown we have to convert a strong reference to
// a weak reference to force the deferring behavior if the user's finalizer
// happens to delete this reference so that the code in this function that
// follows the call to the user's finalizer may safely access variables from
// this instance.
if (is_env_teardown && RefCount() > 0) _refcount = 0;
if (_finalize_callback != nullptr) {
// This ensures that we never call the finalizer twice.
napi_finalize fini = _finalize_callback;
_finalize_callback = nullptr;
_env->CallFinalizer(fini, _finalize_data, _finalize_hint);
}
// this is safe because if a request to delete the reference
// is made in the finalize_callback it will defer deletion
// to this block and set _delete_self to true
if (_delete_self || is_env_teardown) {
Delete(this);
} else {
_finalize_ran = true;
}
}
template <typename... Args>
Reference::Reference(napi_env env, v8::Local<v8::Value> value, Args&&... args)
: RefBase(env, std::forward<Args>(args)...),
_persistent(env->isolate, value),
_secondPassParameter(new SecondPassCallParameterRef(this)),
_secondPassScheduled(false) {
if (RefCount() == 0) {
SetWeak();
}
}
Reference* Reference::New(napi_env env,
v8::Local<v8::Value> value,
uint32_t initial_refcount,
bool delete_self,
napi_finalize finalize_callback,
void* finalize_data,
void* finalize_hint) {
return new Reference(env,
value,
initial_refcount,
delete_self,
finalize_callback,
finalize_data,
finalize_hint);
}
Reference::~Reference() {
// If the second pass callback is scheduled, it will delete the
// parameter passed to it, otherwise it will never be scheduled
// and we need to delete it here.
if (!_secondPassScheduled) {
delete _secondPassParameter;
}
}
uint32_t Reference::Ref() {
uint32_t refcount = RefBase::Ref();
if (refcount == 1) {
ClearWeak();
}
return refcount;
}
uint32_t Reference::Unref() {
uint32_t old_refcount = RefCount();
uint32_t refcount = RefBase::Unref();
if (old_refcount == 1 && refcount == 0) {
SetWeak();
}
return refcount;
}
v8::Local<v8::Value> Reference::Get() {
if (_persistent.IsEmpty()) {
return v8::Local<v8::Value>();
} else {
return v8::Local<v8::Value>::New(_env->isolate, _persistent);
}
}
void Reference::Finalize(bool is_env_teardown) {
if (is_env_teardown) env_teardown_finalize_started_ = true;
if (!is_env_teardown && env_teardown_finalize_started_) return;
// During env teardown, `~napi_env()` alone is responsible for finalizing.
// Thus, we don't want any stray gc passes to trigger a second call to
// `RefBase::Finalize()`. ClearWeak will ensure that even if the
// gc is in progress no Finalization will be run for this Reference
// by the gc.
if (is_env_teardown) {
ClearWeak();
}
// Chain up to perform the rest of the finalization.
RefBase::Finalize(is_env_teardown);
}
// ClearWeak is marking the Reference so that the gc should not
// collect it, but it is possible that a second pass callback
// may have been scheduled already if we are in shutdown. We clear
// the secondPassParameter so that even if it has been
// scheduled no Finalization will be run.
void Reference::ClearWeak() {
if (!_persistent.IsEmpty()) {
_persistent.ClearWeak();
}
if (_secondPassParameter != nullptr) {
*_secondPassParameter = nullptr;
}
}
// Mark the reference as weak and eligible for collection
// by the gc.
void Reference::SetWeak() {
if (_secondPassParameter == nullptr) {
// This means that the Reference has already been processed
// by the second pass callback, so its already been Finalized, do
// nothing
return;
}
_persistent.SetWeak(
_secondPassParameter, FinalizeCallback, v8::WeakCallbackType::kParameter);
*_secondPassParameter = this;
}
// The N-API finalizer callback may make calls into the engine. V8's heap is
// not in a consistent state during the weak callback, and therefore it does
// not support calls back into it. However, it provides a mechanism for adding
// a finalizer which may make calls back into the engine by allowing us to
// attach such a second-pass finalizer from the first pass finalizer. Thus,
// we do that here to ensure that the N-API finalizer callback is free to call
// into the engine.
void Reference::FinalizeCallback(
const v8::WeakCallbackInfo<SecondPassCallParameterRef>& data) {
SecondPassCallParameterRef* parameter = data.GetParameter();
Reference* reference = *parameter;
if (reference == nullptr) {
return;
}
// The reference must be reset during the first pass.
reference->_persistent.Reset();
// Mark the parameter not delete-able until the second pass callback is
// invoked.
reference->_secondPassScheduled = true;
data.SetSecondPassCallback(SecondPassCallback);
}
// Second pass callbacks are scheduled with platform tasks. At env teardown,
// the tasks may have already be scheduled and we are unable to cancel the
// second pass callback task. We have to make sure that parameter is kept
// alive until the second pass callback is been invoked. In order to do
// this and still allow our code to Finalize/delete the Reference during
// shutdown we have to use a separately allocated parameter instead
// of a parameter within the Reference object itself. This is what
// is stored in _secondPassParameter and it is allocated in the
// constructor for the Reference.
void Reference::SecondPassCallback(
const v8::WeakCallbackInfo<SecondPassCallParameterRef>& data) {
SecondPassCallParameterRef* parameter = data.GetParameter();
Reference* reference = *parameter;
delete parameter;
if (reference == nullptr) {
// the reference itself has already been deleted so nothing to do
return;
}
reference->_secondPassParameter = nullptr;
reference->Finalize();
}
} // end of namespace v8impl
// Warning: Keep in-sync with napi_status enum
static
const char* error_messages[] = {nullptr,
"Invalid argument",
"An object was expected",
"A string was expected",
"A string or symbol was expected",
"A function was expected",
"A number was expected",
"A boolean was expected",
"An array was expected",
"Unknown failure",
"An exception is pending",
"The async work item was cancelled",
"napi_escape_handle already called on scope",
"Invalid handle scope usage",
"Invalid callback scope usage",
"Thread-safe function queue is full",
"Thread-safe function handle is closing",
"A bigint was expected",
"A date was expected",
"An arraybuffer was expected",
"A detachable arraybuffer was expected",
};
napi_status napi_get_last_error_info(napi_env env,
const napi_extended_error_info** result) {
CHECK_ENV(env);
CHECK_ARG(env, result);
// The value of the constant below must be updated to reference the last
// message in the `napi_status` enum each time a new error message is added.
// We don't have a napi_status_last as this would result in an ABI
// change each time a message was added.
const int last_status = napi_detachable_arraybuffer_expected;
static_assert(
NAPI_ARRAYSIZE(error_messages) == last_status + 1,
"Count of error messages must match count of error values");
CHECK_LE(env->last_error.error_code, last_status);
// Wait until someone requests the last error information to fetch the error
// message string
env->last_error.error_message =
error_messages[env->last_error.error_code];
*result = &(env->last_error);
return napi_ok;
}
napi_status napi_create_function(napi_env env,
const char* utf8name,
size_t length,
napi_callback cb,
void* callback_data,
napi_value* result) {
NAPI_PREAMBLE(env);
CHECK_ARG(env, result);
CHECK_ARG(env, cb);
v8::Isolate* isolate = env->isolate;
v8::Local<v8::Function> return_value;
v8::EscapableHandleScope scope(isolate);
v8::Local<v8::Value> cbdata =
v8impl::CreateFunctionCallbackData(env, cb, callback_data);
RETURN_STATUS_IF_FALSE(env, !cbdata.IsEmpty(), napi_generic_failure);
v8::Local<v8::Context> context = env->context();
v8::MaybeLocal<v8::Function> maybe_function =
v8::Function::New(context,
v8impl::FunctionCallbackWrapper::Invoke,
cbdata);
CHECK_MAYBE_EMPTY(env, maybe_function, napi_generic_failure);
return_value = scope.Escape(maybe_function.ToLocalChecked());
if (utf8name != nullptr) {
v8::Local<v8::String> name_string;
CHECK_NEW_FROM_UTF8_LEN(env, name_string, utf8name, length);
return_value->SetName(name_string);
}
*result = v8impl::JsValueFromV8LocalValue(return_value);
return GET_RETURN_STATUS(env);
}
napi_status napi_define_class(napi_env env,
const char* utf8name,
size_t length,
napi_callback constructor,
void* callback_data,
size_t property_count,
const napi_property_descriptor* properties,
napi_value* result) {
NAPI_PREAMBLE(env);
CHECK_ARG(env, result);
CHECK_ARG(env, constructor);
if (property_count > 0) {
CHECK_ARG(env, properties);
}
v8::Isolate* isolate = env->isolate;
v8::EscapableHandleScope scope(isolate);
v8::Local<v8::Value> cbdata =
v8impl::CreateFunctionCallbackData(env, constructor, callback_data);
RETURN_STATUS_IF_FALSE(env, !cbdata.IsEmpty(), napi_generic_failure);
v8::Local<v8::FunctionTemplate> tpl = v8::FunctionTemplate::New(
isolate, v8impl::FunctionCallbackWrapper::Invoke, cbdata);
v8::Local<v8::String> name_string;
CHECK_NEW_FROM_UTF8_LEN(env, name_string, utf8name, length);
tpl->SetClassName(name_string);
size_t static_property_count = 0;
for (size_t i = 0; i < property_count; i++) {
const napi_property_descriptor* p = properties + i;
if ((p->attributes & napi_static) != 0) {
// Static properties are handled separately below.
static_property_count++;
continue;
}
v8::Local<v8::Name> property_name;
napi_status status =
v8impl::V8NameFromPropertyDescriptor(env, p, &property_name);
if (status != napi_ok) {
return napi_set_last_error(env, status);
}
v8::PropertyAttribute attributes =
v8impl::V8PropertyAttributesFromDescriptor(p);
// This code is similar to that in napi_define_properties(); the
// difference is it applies to a template instead of an object,
// and preferred PropertyAttribute for lack of PropertyDescriptor
// support on ObjectTemplate.
if (p->getter != nullptr || p->setter != nullptr) {
v8::Local<v8::FunctionTemplate> getter_tpl;
v8::Local<v8::FunctionTemplate> setter_tpl;
if (p->getter != nullptr) {
v8::Local<v8::Value> getter_data =
v8impl::CreateFunctionCallbackData(env, p->getter, p->data);
getter_tpl = v8::FunctionTemplate::New(
isolate, v8impl::FunctionCallbackWrapper::Invoke, getter_data);
}
if (p->setter != nullptr) {
v8::Local<v8::Value> setter_data =
v8impl::CreateFunctionCallbackData(env, p->setter, p->data);
setter_tpl = v8::FunctionTemplate::New(
isolate, v8impl::FunctionCallbackWrapper::Invoke, setter_data);
}
tpl->PrototypeTemplate()->SetAccessorProperty(
property_name,
getter_tpl,
setter_tpl,
attributes,
v8::AccessControl::DEFAULT);
} else if (p->method != nullptr) {
v8::Local<v8::Value> cbdata =
v8impl::CreateFunctionCallbackData(env, p->method, p->data);
RETURN_STATUS_IF_FALSE(env, !cbdata.IsEmpty(), napi_generic_failure);
v8::Local<v8::FunctionTemplate> t =
v8::FunctionTemplate::New(isolate,
v8impl::FunctionCallbackWrapper::Invoke,
cbdata,
v8::Signature::New(isolate, tpl));
tpl->PrototypeTemplate()->Set(property_name, t, attributes);
} else {
v8::Local<v8::Value> value = v8impl::V8LocalValueFromJsValue(p->value);
tpl->PrototypeTemplate()->Set(property_name, value, attributes);
}
}
v8::Local<v8::Context> context = env->context();
*result = v8impl::JsValueFromV8LocalValue(
scope.Escape(tpl->GetFunction(context).ToLocalChecked()));
if (static_property_count > 0) {
std::vector<napi_property_descriptor> static_descriptors;
static_descriptors.reserve(static_property_count);
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